Driveways, walkways and interlock
Concrete and interlock take the worst of a Toronto winter. Salt, sand, oil drips, tire marks and a black film of algae along the shaded edge all sit in the surface pores. A surface cleaner attachment is the right tool here rather than a bare wand: it spins two jets under a shroud, covers a wide path evenly and leaves none of the zebra striping you get from waving a wand about. Oil patches get a degreaser first and a dwell time, because pressure alone pushes oil deeper into concrete instead of lifting it.
Interlock brings one extra step. Washing pulls polymeric sand out of the joints, so those joints need topping up and re-setting afterwards or the pavers start to shift and weeds return quickly. Anyone who leaves an interlock patio with hollow joints has done half a job.
Matching pressure washing to the surface
Every pressure washing job starts with two decisions: how much pressure, and which nozzle. Nozzles are colour coded by spray angle, and the wider the fan the gentler the hit. A narrow red tip belongs almost nowhere on a house. Standoff distance does as much work as the dial, since the same machine is aggressive at ten centimetres and mild at fifty.
- Concrete and interlock: high pressure with a surface cleaner
- Cedar and pressure-treated wood: low pressure, wide fan, kept moving
- Vinyl and aluminium siding: low pressure, always washing downward at the laps
- Brick and mortar: moderate pressure, never a narrow tip at a joint
- Painted or stained wood: a cleaning solution first, then the lightest rinse that works
- Composite decking: manufacturer limits respected, soap and a soft brush for the rest
Testing in a hidden corner takes a minute and settles the argument. I do it on every surface I have not washed before, because a mortar joint or a soft board tells you very quickly what it will tolerate.
Decks and fences without the fuzz
Wood is where most damage happens. Cedar and pressure-treated softwood are soft between the growth rings, and too much pressure blasts that soft wood away, leaving a furry, raised grain that drinks stain unevenly and never looks right again. The correct approach is a wide fan at low pressure, held well back, worked along the length of each board rather than across it, with an even pass so there are no dark stripes where the wand paused.
Grey, weathered wood usually needs a cleaner rather than more force. A deck cleaner lifts the dead surface fibres and the mildew, then a rinse takes it away. Where the boards will be re-stained afterwards, a brightener brings the pH back down and opens the grain so the new stain actually penetrates. Skipping that step is why so many re-stained decks look blotchy by the following summer.
Siding, garage doors and brick
Siding is a rinse, not a blast. Vinyl and aluminium laps are designed to shed water running down, so washing upward under the laps forces water into the wall cavity where it has no way out. Low pressure from above, working down, with a soap applied first and given time to work, takes off the green film and the pollen without soaking the sheathing. Around windows and doors I keep the wand well away from the caulking joints.
Garage doors and painted steel doors clean up beautifully at modest pressure and repay a wax afterwards. Brick and block need more care than people expect: mortar joints are softer than the brick, and a narrow tip held close will cut mortar out of a joint in seconds. Older homes across the Greater Toronto Area with lime mortar get the gentlest setting that does the job, or a soft wash instead.
Before, during and after
Preparation saves trouble. Plants get soaked with clean water and covered where a cleaning solution is in play, outdoor outlets and light fittings get taped, windows get shut and checked, and furniture and the barbecue move off the deck. Runoff needs somewhere sensible to go, which on a sloped city lot is worth thinking about before the machine starts rather than after.
Results are honest, not magical. Pressure washing removes what sits on a surface: dirt, salt film, algae, mildew, moss, cobwebs and loose material. It does not remove rust bleed, deep oil that has soaked in for years, tire scuffing burned into concrete, or the shadow left where something sat in the sun for a decade. I will tell you before I start which marks are likely to lift and which are permanent.
